Casing-spear.



W J. LOUDEN.

CASING SPEAR.

APPLICATIONIFILED 1uLY27.1915.

Patented Feb. 1, 1916."

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CASING-SPEAK.

Specification of Letters Patent.

Patented Feb. 1, 1916.

Application filed July 27, 1915. Serial No. 42,174.

adapting the spear to casings of different;

diameters and avoiding the present usual practice of provldlng adifferent spear for each size. The improved spear is .quite as effectivefor one size as another, and by increasing its range a marked economy inan expensive type of well tool is effected.

The invention is embodied in improved means for adjustably maintainingthe slips at the desired elevation, also improved means foraccomplishing such adjustment.

In the accompanying drawings, Figure 1 is an elevation of the improvedspear. Figs. 2 and 3 are vertical longitudinal sectional views of thesame taken at right angles to each other. Fig. 4 is a cross-section online 4.4: of Fig. 2. Fig. 5 is a cross-section, enlarged, on line 5-5 ofFig. 3. Fig. 6 is a sectional detail of the adjustable slip-holdingmeans.

Referring to the drawings, 2 designates the body of the spear havingaxial bore 3 extending upwardly from its lower end, the bore beingclosed by plug 1. At opposite sides of the body are the downwardlycliverging slipways 5, each provided with a central longitudinal groove6 of dove-tail section. 7 are the wedging slips of usual construction inthis type of tools which are slidable on ways 5, the inner faces of theslips formed with holding ribs 6' complementary with and fitting the.grooves 6. The outer faces of the slips are serrated at 7 for securing abiting hold on theinterior of the casing to be elevated. The upper endsof ways 5 terminate in shoulders 8 which overhang theslips, and abovethese shoulders the body is provided with wrench hold 9. Projecting fromthe upper-end of the body is the usual coupling pin 10. i In thepreferred construction the entire body, in-

cluding wrench hold 9 and pin 10, is a single ways 5 with the ends ofthe key entered loosely in slots 14: of slips 7. Interposed between thelower extremity of stem 11 and plug 4 is the expansible coiled spring 15which opposes depression of the stem and slips and when the stem isreleased operates to raise the latter and the slips to the upperportions of ways 5, thereby contracting or drawingin the slipsandreleasing their hold on the casing.

When setting the slips it is desirable to retain them at such .elevationon the ways as will causetheir serrated faces 7 to just clear the innerface of the casing on the downward movement but'which' will impinge thecasing on the slightest upward movement, the sloping under faces ofserrations 7 and their horizontal or abrupt upper facesproducing thisratchet-like effect. For thus accurately holding the slips for eachdifferent size casing, stem 11 is provided with the vertical series ofhorizontal toothlike serrations 16 whichare preferably continuous aroundthe stem excepting for the interruption caused by vertical rack 17 atone side thereof. A. horizontal opening 18 in one side of body 2 isadapted to accommodate the latch-like bolt 19 having its outer extremityaccessible for pressing the latch inwardly into engagement with the stemin opposition to spring 20 which holds the latch normally out ofengagement with the stem. The preferred form of serrations and latchdeviceare illustrated in detail in Fig. 6, each serration having asloping under .surface and a top surface that is slightly dished at 16.so that it will provide a secure hold for the. curved and beveledextremity 19 of latch 19, said extremitybeing slightly hooked as shownto more securely engage the dished serration. The" machine work incidentto producing serrations 16 is not increased by reason of the fact thatthey are extended almost entirely around the stem as they are simplyturned up in a lathe, and by thus forming them the latch device need notbe located in the body with exact precision. I

In the adaptation shown, rack 17 is engaged by pinion 21 located indepression 1 22 diametrically opposite the latch device, the arbor 23 towhich the pinion is secured being confined in a suitable passage formedin body 2 and having a head'23 to which a wrench or other turning devicemay be conveniently applied. By this means the stem may be lowered asdesired for setting the slips at the most advantageous elevation for theparticular size of casing to be operated upon, and when that position isreached, latch device 19 is projected inwardly in opposition to spring20 and engages the appropriate serration 16 for holding the stem andslips. Having thus ad'- justed the spear for a casing of particulardiameter it is passed downwardly thereinto to a point where it isdesired to secure a hold, and with the slips set to justclear the casingon the downward movement, slight upward movement of the spear will causethem to impinge the casing and thereby lower the slips and stem inopposition to spring 15 sufficiently to relax the hold of latch device19, whereupon the latter is projected outwardly automatically bv spring20, thereby tripping the spear. The slips may extend downwardly andoutwardly as far as may be necessary under the continued upward pull onbody 2, the effectiveness of the hold of course increasing with thepulling force exerted on the tool, and the casing is therebv withdrawnunless it has become too solidly fixed in the well. If impractical toloosen it by proper manipulation of the spear, slight downward movementof the latter relaxes the wedging action, and with latch device 19retracted and out of the way the slips are forced upwardly to shoulders8, their position being thereby so contracted on the tool body that thespear may be withdrawn without obstruction.

The tool is of simple construction, the bodv being preferably formed ofa single forging, and with the range of adjustment as herein providedthe spear may be adapted. to casings of various diameters, avoiding thenecessity of providing a different spear for each size as is nowordinarily the praotice.

I claim:

1. In a casing spear, the combination of a hollow tool body havingdownwardly cliverging slipways, slips movable on said ways, a stemmovable in the bodv cavity longitudinally of the slipways and.operatively connected to the slips for raising and lowering them, aspring for opposing downward movement of the stem and slips, meansmounted in the tool body and operatively connected to the stem forlowering it and the slips in opposition to said spring, andautomatically releasable means for main taining the slips in depressedposition.

2. The combination of a hollow tool body having downwardly divergingslipways, opposed slips movable on said ways, a stem movable verticallyin the body and operatively connected to the slips for holding themelevated, a spring for opposing downward movement of the stem, the stemprovided with a vertical series of notches, a latch device carried bythe body and adapted to engage one or another of the notches for holdingthe stem depressed, a spring for opposing movement of the latch devicein direction to engage the stem and adapted to disengage the latchdevice therefrom upon counteracting the upward pressure of thestem-holding spring, the stem provided with a vertical rack, and apinion mounted on the body and meshing with said rack for lowering thestem in opposition to its hold ing spring.

, 8. The combination of a hollow tool body having downwardly divergingslipways, opposed slips movable on the ways, a stem movable verticallyin the body and operatively connected to the slips, the stem formed atone side with a vertical rack and with a vertical series of horizontaltooth-like serrations extending around a portion of the stem notoccupied by the rack, the body formed with an externallyopen latchway, alatch device movable in said way with its inner extremity shaped toengage one, or another of said stem serrations for holding the stemdepressed, a spring for opposing stem-engaging movement of the latchdevice and for disengaging said device from the stem, a spring foropposing downward movement of the stem and. for raising the same whenthe latch device is released, and stem depressing means adapted tocooperate with said ver tical rack.

4. The combination of a hollow tool body having downwardly divergingslipways, opposed slips movable on said ways, a stem movable verticallyin the body and operatively connected to the slips, a spring foropposing downward movement of the stem, the stem provided with avertical rack, a pinion rotatably mounted in the body and meshing withthe rack for lowering the stem in opposition to said spring, and anautomatically releasable latch device for holding the stem in depressionposition.

5. In a casing spear, the combination of a tool body having oppositedownwardly diverging slipways, slips movable on said ways, the bodyformed with a cavity and a matically releasable means for maintainingdevice movable in the cavity and connected the slips in depressedposition. 10 to the slips for raising and lowering them, In testimonywhereof I affix my signaa spring for opposing downward movement ture inpresence of two witnesses.

of said device and for holding it and the WILLIAM J. LOUDEN. slipsnormally elevated, means mounted in Witnesses:

the body for depressing the slip-holding de- W. A. LOUDEN,

vice in opposition to said spring, and auto SARAH O. LOUDEN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. C.

